Results: The median follow-up duration was 27.5 months (3-73 months) and mean age was 42 years. With 230, 214, 180, 142, 88, 42 and 11 patients followed-up for at least 3 months,6 months, 1, 2, 3, 4 and 5 years, respectively. In all, Incremental increases were observed in the rates of undetectable HBV DNA. 67.0%, 85.0%, 89.4%, 94.4%, 95.5%, 97.6%, 100% had undetectable HBV DNA at month 3, month 6, 1 year, 2 years, 3 years, 4 years and 5 years. Proportions of patients achieving normal ALT were 73.9%, 85.5%, 82.8%, 89.4%, 80.7%, 85.7%, 100%, respectively. The rate of HBeAg seroconversion reached 21.4% and 15.4% at year2, 3, respectively. One patient achieved HBsAg seroclearance after 1 year, and achieved anti-HBs seroconversion at year 3. Of 180 patients, HBV DNA was detectable (partial virological response, PVR) in 19 patients at year 1 of follow-up, twelve of 14 (85.7%) patients with PVR need more than 1 year of continuous ETV therapy to achieved VR. At baseline, no ETV-resistance was detected in 25 ETV-naïve patients. One patient developed ETV-resistance mutations due to noncompliance. No serious adverse event was reported.

Conclusion: Long-term ETV treatment of nucleos(t)ide-naïve was effective and safe in real life. Adjustment of ETV monotherapy in nucleos(t)ide-naïve patients with a partial virological response at 1 year may be unnecessary.